Fuel feeding system with combined valve and air vent



July 29,1941 s. E. HEYMANN 2,424,754

Y FUEL FEEDING SYSTEM WITH COMBINED VALVE AND AIR VENT Filed July 29,1942 I Q :y x A 'l f s #FFI *Y 6 iiiiii w 11 N Ir- A -j/l gi w mr u. IA@ e k y f w w w' N 1 :s s j' w FL! N Q Nm l N 1\ Vf/ XG" j iv"'aaernszgrv j l Ig limmuumumuuf/l// W :Q as 1 kiiiiaa'aas LL :e @a

5/ @1w/mf man )g s Pateniecl July 29, i947 UNITED STATES PATENT OFFICEFUEL FEDING SYSTEM WITH COMBINED VALVE AND AIR VENT Seymour E. Heymann,Chicago, Ill., assignor to Stewart-Warner'Corporation, Chicago, Ill., a

corporation of Virginia Application July 29, 1942, Serial No. 452,713

My invention relates to fuel feeding systems and is more particularlyconcerned with the gasoline supply line for an internal combustionheater installed in an airplane.

In modern airplane practice, it is common to locate internal combustionheaters in various parts of the airplane fuselage and to supply theseheaters with gasoline from the main fuel tanks of the airplane. In manyinstances the heaters are located at considerable distances from theAnother object of my invention is to provide a.

fuel feeding system for an internal combustion heater or similar deviceand wherein the fuel feeding pipes or conduits will be drained of fuelexcept when the heater or similar device is in actual operation.

.Another object of my invention is -to provide a fuel feeding system ofthe kind hereinabove indicated which may be easily installed and whichwill not increase the weight over existing fuel feeding systems.

Another object of my invention is to provide a new and improved fuelfeeding system which' can be easily embodied in present fuel feedingsystems by a few simple modifications thereof.

Other objects and advantages will become apparent as the descriptionproceeds.

In the drawings, Fig. 1 is a diagrammatic representation of a part of anairplane having a preferred embodiment of my invention applied thereto,and Fig. 2 is a sectional view on an enlarged f scale of the solenoidvalve of Fig. 1.

In the drawing I have indicated an airplane having a fuselageV III and awing I2 provided with one or more main fuel tanks I4 for supplyinggasoline to the engine or engines which propel the airplane. The fueltank yI4 is also utilized as a source of fuel `for one or more internalcombustion heaters I6 which may be located at a lower level and atrelatively great distances from the fuel tank I4. The internalcombustion heater I6 may be of any conventional or usual type and isillustrated as being located in a duct I8 through which air is forced bya. blower 2i! driven by any 8Claims. (Cl. 15S-42.4)

j space which it is desired to heat.

used in place of the blower in many installations. The air discharged bythe blower 20 flows over the heat exchange ns of the heater I6 andthence through the duct I8 tothe cabin, or other It will be understoodby those skilled in the art that the internal combustion heater I may beprovided with the usual controls and may be of any size necessary toaccomplish its desired purpose. The

j particular location of the heater I6 is for illustrative purposes onlyand the location of the heater or' heaters will vdepend upon the type ofairplane .and the number of heaters installed therein.

1B Fuel is withdrawn from the tank I4 by a fuel.

pump P discharging into a pipe 22 leading to a carburetor 24 whichsupplies the heater I6 with a combustible mixture of gasoline and air.The carburetor 24 receives its supply of air through 90 an inlet V2liconnected to the discharge side of the blower 20 and diverting a smallportion Aof the air discharged by this -blower to the carburetor inlet.The combustible mixture formed in the carburetor passes through inletpipe 28 to 25 heater I6 where itis burned and the products of combustionformed in the heater are dischargedl through an exhaust pipe having anoutlet end 32 preferably, but not necessarily, arranged to create asuction in the heater I 6.

80 In the normal operation of the apparatus, the

flow of gasoline to vthe heater IBAis controlled by the solenoid valve34 located in the pipe 22. This valve is connected by wire 36 and switch38 to a battery 40 illustrated as grounded at 42. In lieu of the battery40, any other suitable source of electrical current may be utilized.

The solenoid valve 34, as shown more clearly in Fig. 2, is of the typewherein the valve member 33 is normally'urged by a spring 35 towardsclosed position and wherein this valve member is held in open positionagainst the force of this Yspring only while the solenoid 39, 4I isenergized. The valve 34 has an air inlet 3l which is closed when thevalve member is in open position. When the valve member is in closedposition, the inlet 43l' is in communication with that part of the pipe22 which connects the valve 34 with the carburetor 2U, but is cut ofifrom communication with that part of pipe 22 which connects the valve'34 and pump P.

I have also shown an emergency'valve 44 as being located in the pipe 22adjacent the car'- buretor 24. The valve 44 is also a solenoid valve andhas a valve member biased toward open posisuitable means. An air scoopor r-am may be tion by theusual spring. The valve member is any suitablesource.

heid in closed position only while the solenoid is energized. The valve44' has no air inlet corresponding to the inlet 31 of valve 34. A wire48 connects solenoid valve 44 to an overheat switch 48 which is normallyopen but which closes when the air in that part of'duct I8 adjacent thisswitch reaches an abnormally high temperature.

'I'he voverheat switch 48 and emergency solenoid valve 44 may besupplied-with current from trated in the drawing, Ihave shown thissource as a battery which is connected to the overheat switch 48 throughwire 58 and switch 38. It will be understood that the heater I 8 isprovided with the usual ignition circuit and controls therefor and maybe provided with any other In the embodiment illus-4 usual or suitablecontrols for regulating the heat output or other operatingcharacteristics of the heater.

When the heater I6 is not operating, that part of pipe 22 which connectsvalve 34 with carburetor 24 is in open communication with air inlet 31and is entirelyempty of gasoline. If it is Vdesired to start the heater,switch 38 is closed, thereby energizing thesolenoid in the solenoidvalve 34. Emergency valve 44 remains open. Simultaneously, orsubstantially so, blower 28 is started and the igniting means of theheater I8 is putinfcondition to ignite any combustible mixture suppliedthereto. y

`In the embodiment shown in the drawing, I have illustrated the fuelpump P as being an 'electric fuel pump which is supplied with currentthrough a wire 52 connected to battery l4|I through switch 38 so thatthe pump 1i' will be energized simultaneously with the opening ofsolenoid valve 34. Where the pump P is utilized to supply fuel to otherheaters or other equipment, additional controls will, of course, beprovided so that the operation of the pump P will conform to the needsof all of the equipment to which it supplies fuel. The pump P need notbe an electrically operated pump but may be a mechanically driven pumpor any other suitable means for withdrawing fuel from tank I4 andforcing the fuel through piping to the point or points where it isutilized.

Energization of the solenoid in solenoid valve 34 opens this valve,thereby providing free communication between the portions of pipe 22 onopposite sides of this valve and also closing the air inlet 31. Fueldischarged by the pump P ilows rapidly into the pipe 22 and in a verybrief interval completely lls this pipe and reaches the carburetor 24.In the meantime, air in pipe 22 has been sucked into carburetor 24through heater I6, which, of course, does not start to operate untilsupplied with a combustible miarture.

When the gasoline flowing into pipe 22 reaches carburetor 24, thisgasoline is mixed with air and the combustible mixture thus formed Howsthrough pipe 28 to heater i6, where it is ignited and gives up itsheated air forced over the heater 'by blower 28. 'I'he products of-combustion from the heater are discharged to atmosphere through pipe30. 'I'he heated air in the duct I8 is utilized to heat a cabin or otherspace in the airplane or for any other desired purpose and any usual orsuitable control means may be provided to regulate the temperature ofthe heated air.

If the air in duct I8 adjacent overheat switch 48 reaches apredetermined abnormally high temperature, switch 48 closes. Thisenergizes the solenoid in emergency valve v Furthermore, the fuel anddischarged 'with air under pipe and adjacent th 4 this valve to cut oil'the supply of fuel to the carburetor 24 and heater I6. As soon as thetemperature adjacent the switch 48 has dropped to a safe value, switch48 opens and emergency valve 44 again assumes its normally openposition. Fuel again flows to carburetor 24 and is ignited in heater I8,which assumes its normal operation. When itis desired to shut off theheater I6,

switch 38 is moved to open position. This deenergizes the lsolenoid invalve 34 and permits the valve member therein to cut off communicationbetween the pump P and that part of pipe 22 which connects valve 34 withcarburetor 24. This shift in the valve member of valve 34 connects inlet81 with that part of pipe 22 which connects this valve with carburetor24 and heater Il continues to operate until all fuel hasbeen withdrawnfrom this part of pipe 22.

Heater I6 thereupon ceases to operate and blower .28 should then bestopped through any suitable manual or `automatic control means, as

for example, when the'blower 2li is electric motor driven, a temperatureresponsive switch in the motor circuit may be located so that it opens-whenever the heater becomes cold. Thus the blower 28 may continue tooperate for a brief period after the' flow of combustible mixture to theheater I8 has ceased in order to dissipate heat stored up in the body ofthe heater itself.

As long as the switch 38 remains open. that part of the fuel supply linewhich lies between valve 24 and heater I8 contains no gasoline but isfilled atmospheric pressure. Any damage to this part of the fuel supplyline during thisperiod` would not result in leakage of gasoline. It isonly during actual operation of the heater that the main portion of thefuel supply line for the heater contains gasoline.

In the embodiment of my invention selected for purposes of illustration,the carburetor is supplied with air from the blower 20 and this blowervalve I4 is closed. y

An important feature of my invention lies in thefact that my new andimproved fuel feeding system is simple and easily installed and adds noweight tothe fuel feeding systems now in use. feeding systems now in usecan easily be convertedto embody my invention and thereby materiallyreduce the fire hazard in airplanes utilizing these fuelfeeding'systems.

The embodiment shown in the drawing is illustrative only and myinvention is not limited to the details shown and described but issusceptible to numerous variations` and modifications coming within thescope of the appended claims.

I claim:

l. A i'uel feeding system for supplying an internal combustion heater ofan airplane with fuel from a fuel tank located at a distance from theheater comprising a relatively long pipe connecting said tank andheater, a valve between said tank and ,tank for controllingcommunication between said tank and pipe, control means for opening andclosing said'valve, and an air inlet for said pipe controlled by saidvalve, said air inlet being above said pipe.

2. A fuel feeding system for supplying an in- '44 and causes 'ternalcombustion heater of an airplane with ltance from the heater, comprisinga relatively long pipe, an inlet valve for said pipe controllingvcommunication between said pipe and said source of fuel supply, andvent means controlling communication between said pipe and atmosphereautomatically to admit air to said pipe when said valve is closed and toexclude air from said pipe when said valve is open, said vent meanscommunicating with atmosphere at a point higher than any part of saidpipe.

3. A fuel feeding system for supply an. internal combustion heater of anairplane with fuel from a source located at a substantial distance fromthe heater, comprising a relatively long pipe connecting .said heaterwith said source of fuel supply, a valve adjacent the inlet end of saidpipe for controlling flow of fuel therethrough, vent means Iabove saidpipe for admitting air lto said pipe when said valve is closed and forexcluding air. from said pipe when said v`valve -is` open, anda commoncontrol means for said valve and vent means.

4. In a fuel feed system for supplying an internal combustion heater ofan airplane with fuel from a source located at a substantial distancefrom the heater, comprising a relatively long pipe connecting saidheater with said-source of fuel, a valve member adjacent the said sourceat the inlet end of said pipe for controlling flow therethrough, meansinterposed between said valve member and heater and adjacent said valvevalve member is in closed position and for excluding air from said pipewhen said valve member is in open position, and -a control circuit forlsaid lastnamed means and valve member, said circuit including a switchfor closing said valve member prior to stoppage of said heater due tolack of fuel.

5. A fuel feeding system for supplying an internal combustion heater ofan airplane with fuel from a fuel tank remote from the heater, com--prising a pipe of substantial length extending through most of thedistance from said tank to said heater, a fuel valve controllingcommunication between said tank and said pipe and located adjacent thetank, and vent means which is closed when the valve is opened and whichis opened by the closing of the valve, said vent means being` in saidpipe adjacent said valve and admitting atmosphere at a point higher thanany part of said pipe.

' member for admitting air to said pipe when said 6. In a fuel feedingsystem as defined in claim 5, electrical means operative to hold saidvalve open when energized, and an electrically driven pump interposedbetween the tank and the valve and connected in the same circuit withsaid valve,

and switch means controlling said circuit 7. In a fuel feeding system asdefined in claim' 5, an electric circuit which includes means operativeto hold the fuel valve open when the circuit is closed and to allow saidvalve to .close when said circuit is opened, a biased and normally openemergency valve in said pipe adjacent the heater, electrically operablemeans for closing said emergency valve, an actuating circuit thereforand a common control switch for both circuits, whereby the opening ofsaid switch causes the fuel valve to close and insures the opening ofthe emergency valve and vents the said pipe to atmosphere.

8. In a fuel feeding system as defined in claim- 5,.an electric circuit.which-includes. means op-4 erative to hold the fuel valve open whenthe.circuit is closed and to allow said valve to close when said circuit isopened, a biased and normally open emergency valve in said pipe adjacentthe heater, electrically operable means for closing said emergencyvalve, an actuating circuit therefor including a thermally operableswitch which closes said circuit in response to a. predeterminedtemperature produced by the heater,

and a common control switch for both vcircuits operable at will,`whereby the opening of said switch causes the fuel valve to close andcauses the emergency valve to open if already closed by said thermalswitch and vents the said pipe to atmosphere. v

l SEYMOUR EDW. HEYMANN.

REFERENCES crran The following references are of record .in the file ofthis patent:

UNITED STATES PATENTS Number

